I believe that a 1 x 12 combo + a 1 x 12 cab would sound as full if not fuller than a 2 x 12. Separate 1 x 12's place the 12's farther apart and you can place them side by side and point one at a slightly different angle than the other. You can get more body to the sound from this. This is not a combo + another 1 x 12 - this is a head and two 1 x 12 cabs but I gigged these side by side with the cabs at different angles and it sounded bid when I walked around. I think you'd love separate 12 cabs (combo + a cab).